Signaling system for elevators



July 12, 1 27. 1,635,586

W. 5. SMITH v SIGNALING SYSTEM FOR ELEVATORS 1 Nov. 2;. 1922 PatentedJuly 12, 1927.

i UNITED, STATES PATENT OFFICE. I

WILLIAM s. SMITH, or" CAMBRIDGE, MASSACHUSETTS.

SIGNALING SYSTEM FOR ELEVATORS.

Application filed November 23, 1922. Serial No. 602,759.

I This invention relates to av signaling systern for electricallycontrolled .elevators,

' hoists and dumb-waiters.

.The main object of theinventlon is the provision of a simple,inexpensive, reliable and efficient signaling system which will indicateatall times the stage of operation or inoperation of the, elevator orhoist.

Other objects of the invention will be more specifically set forth anddescribed hereinafter. 1

My invention in its preferred embodiment contemplates the provisionof aplurality of 2 groups of lights indicating various phases of operationof the elevator car or hoist,

,each group comprising a light at each floor landing and all the lightsin each group'having the same distinctive color. The first group isdesigned to indicate whether or not the car is in operation and all thelights in this group remain illuminated onlyso long as the car is inmotion." The second-group indicates the limit of movement of the car and:iS so arranged that when the car is started towarda certain floor, thelight or this group on that particular floor only is illuminated untilthe car reaches its destination'and the door at that landing is opened.

The third group indicatesthat the car has arrived at its destination or1 is at a landing and all the lights in this group remain illuminateduntilthe door atv the landing is opened. The'fourth group indicateswhether 7 or not the system is out of operation and all are lightedwhenever andso long as it is out of operation. Preferably these latterlights should be red in'color as a warning to one attempting to use'thesystem.

In the accompanying drawings, illustratingthe preferred embodiment of myinven-' tion, is shown a diagrammaticview of asignaling system embodyingmy inve'nt 'on applied" to an electrically controlled elevator system;the latter system, being shown in 'lightlines, and the former system inheavy lines. I

In "the drawings, the apparatus is shown as actuated by a directcurrent, but, with proper modifications all of which will be apparent toone familiar with theqart, the

system may be used in connection with an alternating current. Althoughthe elevator system 18 shown as hav ng three stations or floors it isapparent that this number may be increased or decreased as desired.

For purposes of illustration, I have shown my invention applied to anelectrically controlled eievator system, which system may bebriefly'deseribed first. Referring to the drawings, the positive andnegative supply lines are designated as 3 and 4 respectively and5 is thearmature of a motor, shown as a shunt motor, having a field coil 6connected to the said supply lines by conductors 7 and 8 respectively. Acircuit across the line through conductors 10 and '11 havingstarting'resistance 12 is provided for operating as motor, this circuitbeing closed and opened. by a reversing switch to be hereinafterdescribed.

The operation of the motor though the reversing switch is controlledfrom the various floors or stations by push-buttons 14, 15 and 16, oneat each floor and when'the elevator car carries passengers a similarseries of push buttons 17, 18 and 19 is installed in the car. Thehoistway doors, one on each floor, may be provided with contacts, 20, 21

"and 22 respectively, all included in the push- -button circuits, sothat unless all the hoistway doors are closed the system is out ofoperation.

Arranged to be operated by the pushbutton circuits are a series of floormagnets 24, 25 and26, corresponding in number to j atedand the actuatingcoils being each includedin' circuit with its respective pushbuttonso'that the operation of a push-button energizes its respectiveactuating-coil only.

Whenever a push-button at a floor landing is operated, it closes acircuit from the main 3, through conductor 34, door contacts 20, 21 and22, conductor 35, retaining coils lid 31, 32 and 33, thence through theactuating coil corresponding to the push-button actuated, through one ofthe conductors 36, 37 or 38, to the push-button operated and throughconductor 39 to the negative side of the line. An adjustable resistance4:0 may be included in the conductor to permit of convenient adjustmentof the current in the retaining coils.

The magnets, 21. 25 and 26 carry contactmembers 11, 42, and 13respectively adapted to engage pairs of contacts -14: and 15, 16 and -17and 18 and 19, respectively, to close various control circuits whichdirect the current to the reversing switch in such manner as to startand to stop the motor as desired. The control circuits are divided intotwo groups, one to cause the car to descend and the cthcr to ci'i ectits ascent.

In the first group of control circuits are arranged the contacts 14,4-5, 16 and 17 and switches and 51 and in the second group the contacts16, -17, 18 and =19 and switches 52 and 53. The switches are operated bya suitable controller or member 54 which moves on a screw-rod 255 insynchronism with the car and as shown in the drawing moves to the rightwhen the car is ascending and to the left when it is descending.

The r versing-switch, which may be of any suitable design, isillustrated diagrammatically in the drawing as made up of two magnets 55and 56, each provided with necessary contacts for closing the motorcircuit. The magnet 55 is included in the first group of controlcircuits and the magnet 56 is in the second group. The former magnetcarries contact-pieces 5S and 59 which, when tiie magnet is energized,are moved into engagement with contacts 60 and 61 and 62 and 63respectively to close the motor circuit and to admitcurrent to the motorin such manner as to cause the car to descend. Similar contactpieces 64and 65 are, by the operation of magnet 56, thrown into engage ment withcontacts 66 and 67 and 68 and (39 respectively thereby closing the motorcircuit in such a way as to cause the car to ascend.

The control circuits may be arranged in any suitable manner and one sucharrangement is shown in the drawings. From the positive main 3 all thecontrol circuits use a common conductor up to the contacts 44, etc.comprising conductor 3%, door contacts 20, 21 and and conductor 70 whichis connected to contacts at-il, i6 and 48. Between the contact members4.1, l2 and 13 and the switches 50. 51, 52 and 53 the circuits are bothparallel and common; contact 45 being connected by conductor 72 withswitch 50 which in turn connected to switch 51 by conductor 78; contact-17 being connected by conductor 7 3 to contacts 80 and 81 and contact19 being connected by conductor 74 to switch 53 which is in turnconnected to switch 52 by conductor 79. Conductors 72 and '43 are in thelust or down group of circircuits uses a connnon conductor 76 fromcontact 83 through magnet, 56 :and conductor 77 to the negative main 1.In the drawings the ca r is shown at the second floor with both switches51 and 52 open and therefore the operation of a push-button at thesecond floor produces no efl'ect because no control circuits can beclosed through those switches. Switches 50 and are shown closed,however, and the operation of a pushbutton at either the first or secondfloor will close a control circuit and start the car.

In order to prevent interference with the movement of the car before ithas reached its destination by the pressing of a. second push-button.the actuating coils 28, 29 and 30 and push-buttons are short circuitedwhile the motor is in operation, leaving the retaining coils 31. and 33in the circuit. This is accomplished by providing contacts 8T and 85adapted to be engaged by contact members 58 and 6 1- respectively of thereversing switch; said contacts being connected to conductor 35 at point86 by conductor 87.

The foregoing controlling system for electric elevators is fully shownand described in United States Letters Patent No. 1,228,075 issued to melviay 29, 1 917, to which reference may be made for a more completedescription of the same and its mode of operation.

The novel features of my invention reside in the signaling system, oneembodiment of which is shown for illustrative purposes only as appliedto the foregoing controlling system.

The first group of signals is designed to indicate whether or not thecar is in operation or motion and for this purpose any suitable meansmay be provided whereby these signals are controlled by themotorcontrolling means. One such means is shown in which the reversingswitch is utilized for this purpose. The three lamps 88, 89 and 90 ofthis group. one at each floor station, are placed in series in a circuitcomprising a conductor 91 from the main 3, lamps 88, 89 and 90,conductor 92 either contact 93 member 64: or contact 94 and contactmember 58 to conductor 11 and to the negative main 4. Suitableresistance 95 may be ineluded. This circuit is closed whenever thereversing switch is operated to start the motor and is opened when themotor stops. The result is that so long as the motor 0pcrates and thecar is in motion, all of the said lamps are lighted. As soon asthe carreaches its destinat-ionandcomes to a stop all of thelights go out." i 1The second group of signals which indicate the destination of the car ispreferably operated by the control-circuits of the elevator system sincebut one lamp is lighted 111 respectively.- From the main 3 a contocontacts 106,108 and 110. 113, 114 and 115 of this ductor 112 runs Thethree lamps 1 group are connected by conductors 116, 117

' operation is as lishing a control circuit through conductor 72 therebyenergizing the relay magnet 100 and 118 respectively to contacts 107,109 and lllrespectively. A common conductor 120 including a resistance121 connects the three lamps to the conductor 122 and main 4. The

follows. Suppose the pushbutton 14 onthe lower floor or 17 in thecar beoperated, the -magnet 24 is closed estabwhichcauses the-contact-piece103 to engage contacts 106-and 107. This closes a circuit from the main3 through conductor v112, contact 106, contact-piece 103, contact 107,and conductor 116, lamp 113,'conductors 120, re-

' sistance 121, conductor 122 to the main 4.

The lamp 113 on the lower floor and only a that lamp in this gr'oupislighted by this circuit. If the ush-button on the second floor'be'operatthen conductor 73 operates magnet 101 anda circuit is establishedthrough conductor '117 to lamp 114 and in case of the thirdfloor,mag-net 102 is Operated by lamp 115 through conductor 118. -Theselampsare connected in parallel since only one is lighted at a time. I

When the car arrivesatits destination the control circuit throughconductor 72, or 73,

. or 74, as the case may be, is opened by the operation ofswitch 50 or51 or 52 or 53. @This will permit the relay magnet which has beenoperated by the closedcontrol circuit to return to inoperative positionand to open I the circuit to the destination, lamp which has" beenilluminated up' to thatpointr Since it is desirable that this signalshould remain illuminated until the door at thatstation has been opened,means are provided for maintaining that circuit closed after the controlcircuit has been openeduntil the station door is opened. This result isattained by providing a series of retainingcoils 124, 125 and conductorf74 and a circuit closed to 126101' the relay magnets 100, 101 and 102,

each coil being of sufiicient strength when energized to retain itsrespective magnet 1n any position 1t may be 111 but not ofsufiicieritstrength to operateit. These retaining coilsmay be energizedby a circuit across the line from the main 3 through conductor 34, doorcontacts, 20, 21 and 22, conductor 35, conductor 127, coil 124, coil125, coil 126, conductor 128, coil 129, conductor 130,

resistance 131, conductor 122 to main; 4. Vhenever one of the relaymagnets 100,101 or 102 is operated by a control circuit, the retainingcoil is .sufiicient to hold it in operated position after the controlcircuit is opened and until the station door is opened,

whereupon all circuits are opened and the relay magnet returns toinoperative position.

The third group of signals indicates'that the car has arrived at itsdestination or is at a landing and all the lamps of this group arelighted and extinguished simultaneously.

This requires that these lamps should be lighted immediately upon thearrival of the car and until the station door has been opened.

One means for accomplishing this end is shown and consists in placingthethree lamps 134,135 and 136 of this group in series in a circuitwhich is broken at two points and in providing means for closing thecircuit at both of these points after the carhas arrived at a landingand until a door is opened. The circuit starts from the main 3 throughconductor 34, door contacts 20, 21 and 22, conductor 35, conductor 137to contact 138 where the first break occurs. It is then resumedatcontact 139 from conductor 140 to contact 141 where the second breakoccurs. The remainder of the circuit is from contact 142 throughconductor143, lamps 136, 135 and 134, conductor 144 ineluding resistance145 and conductor 122 to the main 4. The first break, which is normallyopen, is adapted to be closed by'a contact piece 146 carried by a magnet147 when the said mag-netis energized by a coil 148 inconductor 112.This last conductor is included in the circuit for operating the secondgroup of signals and since that circuit is closed as soon as the carstarts the magnet 147 is operated at that time to close theffirst breakin the circuit for operating the third group andt-he magnet remainsoperative until a door is opened. Under these circumstances and providedthere was no second break in the present circuit, the lamps of the thirdgroup would be illuminated at the time the car started. In order toprevent tbis and to have these lamps illuminated only when the carreaches its destination, the second break is provided, which break isnormally closed by a contact-piece 149. This contact-piece is carried bya magnet 150 which is energized by a coil 151 in conductor lll 70, whichconductor is in the main control circuit. As soon, therefore, as thecontrol circuit has been established by the operation. of a push-button,the magnet 150 is energized by the coil 151 and the contact-piece 149 israised breaking the circuit to the third group of lamps at the secondbreak. \Vhen the car reaches its destination and stops, the controlcircuit is opened, the magnet 150 de-energized and the contact-piece 149drops by force of gravity into engagement with contacts 141, 142,thereby closing the circuit to the third group of lamps and the circuitremains in that condition with the three lamps illuminated until a dooris opened.

It will be observed that in the signaling system so far described all ofthe circuits include the door contacts so that the opening of a doorimmediately opens all of the circuits which may happen at that time tobe closed and causes all of the lights of the first three groups whichhappen to be illuminated to go out and the apparatus to return to thecondition shown in the drawings.

The fourth group of signals is intended to indicate when the elevatorcontrol system is out of operation; that is, when a door is opened at afloor landing, for otherwise the control system is always in operationunless there is a failure of current for some reason or other. Forilluminating the three lamps, 154, 155 and 156 of this group, I providea circuit across the line with the lamps ar ranged therein in series.This circuit is from the main 3 through conductor 91, contact 157,contact-piece 158, contact 159, conductor 160, lamps 156, 155, 154,conductor 161, including the resistance 162 to conductor 122 and main 3.In order to keep this circuit open at all times except when a door isopened, the contact-piece 158 is carried by a magnet 164, which magnetis energized by the coil 129 in the circuit of the retaining coils 124,125 and 126. This circuit is closed whenever all of the doors are closedsince it is across the line through the door contacts. So long,therefore, as all the doors are closed the circuit through saidretaining coils and coil 129 energizes said magnet 164, raises saidcontact-piece 158 and breaks the circuit of the fourth group. Thiscondition continues until a door is opened whereupon the circuit throughsaid coil 129 is broken deenergizing the magnet 164 and permitting thecontact-piece 158 to drop by force of gravity to close the circuitacross the line and to illuminate the lamps of the fourth group, whichlamps remain lighted until all of the doors are closed when the magnet164 is again operated to break the circuit.

Preferably, the lamps of each group should be given a distinctivecoloring in order that they may be differentiated from the other groupsand any suitable colors may be assigned to the first three groups.

For the fourth-group, however, I prefer a red lamp since that isindicative of danger and the fourth group is a warning that the systemis inoperative and should not be interfered with at that time.

The operation of my signaling system is extremely simple and etiicient.Assuming that all the hoistway doors are closed with the elevator at thefirst floor ready for op oration. No signals are illuminated. A persondesiring to use the system on the third floor, for instance, presses thepushbutton on that floor to bring the car to that station. In'imediatelythe first group of lights is illuminated one at each floor, indicatingthat the car is in motion. At the same time that light of the secondgroup which is located at the third floor station is illuminated whichindicates to the person who operated the push-button that the car is onits way to his floor. When the car reaches the third floor and comes toa stop, all of the lights in the first group go out and all of thelights of the third group are illuminated, indicating to the persononthe third floor that the car has arrived at its destination and isawaiting the opening of the door. The person on the third floor uponnoticing the illumination of the light of the third group then opens thehoistw ay door and immediately the lights in the third group and theparticular light at the floor in the second group are extinguished andall the lights in the fourth group are illuminated indicating that thesystem so long as the hoistway door remains open is out of operation.hen the hoist-way door is again closed the red lights are extinguishedand all of the signals remain unlightcd until some action is taken inthe operation of the elevator. The elevator system is ready for use onlywhen there are no signals illuminated. If the red signals are lighted,it indicates that the system is out of operation. If a light of thethird group is illuminated at any floor station, it indicates that thecar is at some floor station demanding attention, having been calledthereto by someone else and that no attempt should be made to operatethe system until a hoistway door has been opened.

Although I have shown my signaling system as utilizing lamps to indicatethe various phases of operation. it is to be understood that these aremerely illustrative since any of the well known forms of indicators suchas bells, buzzers or movable mechanical devices may be employed. In someinstances, it may be desirable to use bells or other audible signalseither alone or in addition to lamps. This is especially true of thesecond group of signals because in this group only one signal is givenat a time and that one on the floor landing to which the car isdestined. To facilitate rapid handling of loo the car an audible signalof destination would be found advantageous since it calls attention tothe fact that the car is ap-' proaching the floor on which the signal is5 sounding, and should insure the immediate 1 of being used inconnection with various forms of electrical control systems nor to theparticular devices and circuits shown and described since it may beembodied in various other forms of construction within the 1 purview ofthe following claim.

What I claim is: The combination with an electrically con- 'trolledelevator system including parallelv control circuits and a plurality ofstations,

of a signal at each station for indicating the destination of the car, adoor at each station,

a plurality of parallel circuits each of which includes one of saidsignals, all of said signal circuits being normally open, a magnetoperated switch for each of: said signal circuits for closing the same,a control circuit for each station including the magnet of the magnetoperated switch for the signal corresponding to that station, means foropening the control circuit upon the arrival of the car atv the stationcontrolling the car, a means for holding said switch in closed positionwhen moved to this position, a door contact vcircuit common to saidparallel control circuits and to said holding circuit including meansoperated upon opening of any of said doors for opening said control andholding circuits.

In witness whereof, I hereunto set my hand this ninth day of November,1922.

WILLIAM S. SMITH.

